Porting XE3 apps to XE4

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Porting XE3 apps to XE4

Work in progress…

Will add comments as I find stuff that breaks.

Published by Lars Fosdal

Software Developer

Published

21 thoughts on “Porting XE3 apps to XE4”

  1. #1 [dcc32 Fatal Error] PSDBase.pas(4003): F2084 Internal Error: C1769

    Cause: “ad hoc” declaration of generic class?

    TSomeClass = class

      FDict: TDictionary; 

    property Dict: TDictionary;

    end;

    …

    i := SomeClassInstance.Dict.Items[ix].BaseClassFunction;  // <– error

    Workaround:

    TDictClass = class(TDictionary<Integer, TBaseClass)

      function WrapperFunction(const ix: Integer):Integer;

    end;

    TSomeClass = class

      FDict: TDictClass 

    property Dict: TDictClass;

    end;

    …

    TDictClass.WrapperFunction(const ix: Integer):Integer;

    var

      BaseClass: TBaseClass;

    begin

      BaseClass := Items[ix] as TBaseClass;

      Result := BaseClass.BaseClassFunction;

    end;

    …

    i := SomeClassInstance.Dict.WrapperFunction(ix);  

        

    Reply

  2. #2 [dcc32 Fatal Error] PSDListViewSelection.pas(945): F2084 Internal Error: G9874

    Interesting!

    Cause: Assigning a different generic list type?  Worked in XE3.

    TSomeClass = class

    strict private

      FList : TList;

    …

    constructor TSomeClass.Create;

    begin

      Inherited

      FList := TObjectList.Create;  // <- Internal error

    Reply

  3. #3 Indy events ><

    Had to add idGlobal to unit.

    Had to change event handler from

    procedure TServerPingThread.OnReceiverRead(

      AThread: TIdUDPListenerThread;

      AData: array of Byte;

      ABinding: TIdSocketHandle);

    to

    procedure TServerPingThread.OnReceiverRead(

      AThread: TIdUDPListenerThread;

      const AData: TidBytes;

      ABinding: TIdSocketHandle);

    and all TBytes references from TBytes to TidBytes.

    Reply

  4. #4 Projects really don’t like units that have not been added to the project – which I think is a good thing.

    I’m an idiot.  Missing semicolon in Library path made the units disappear 😛

    Reply

  5. Do you mean that if you have a library with 100 units, of which only 1 is in your uses (and which uses the 99 other units), you have to place the 100 units in the project?

    Reply

  6. #5: [dcc32 Warning] PSDLocation.pas(620): W1057 Implicit string cast from ‘RawByteString’ to ‘string’

    Cause:

      RegEx.RegEx := UTF8Encode(Loc.NetworkRegExp);

    Workaround – what do I do?

    Opting for:

      RegEx.RegEx := String(UTF8Encode(Loc.NetworkRegExp));

    Reply

  7. #6 [dcc32 Warning] PSDReceiveGoodsHTTPServer.pas(1476): W1000 Symbol ‘ToUpper’ is deprecated: ‘Use TCharHelper’

    Cause

      BooleanVar := (ToUpper(HTML.ParamValue[‘unknownlot’]) = ‘ON’);

    Breaking change:

      BooleanVar := (HTML.ParamValue[‘unknownlot’].ToUpper = ‘ON’);

    Reply

  8. Eric Grange  Not entirely sure, but it certainly looks that way. Don’t know if there is a difference between units referred in the Interface section vs Implementation section.

    Reply

  10. Eric Grange / Heinz Toskano – Ref. Unit inclusion in project.

    I’m an idiot.  It was a missing semicolon in the Library path that made one of my $(COMMON) directories “disappear”.

    Reply

  13. There – now it all builds without hints and warnings.

    So – how are the statistics?

    96 units in total

    2 had Generics related internal errors 

    3 units had “deprecated” warnings – which require breaking changes to suppress.

    – StrPas / StrCopy / StrPLCopy has moved to AnsiStrings unit

    – Indy: TBytes ->TIdBytes

    – ToUpper(str) -> str.ToUpper

    1 unit had a result type change causing a implicit cast warning

    – Non breaking: UTF8Encode -> String(UTF8Encode)

    Less than 40 lines of change – including a small rewrite to work around the Generics Internal Error – out of about 200.000 lines of code.

    Not too bad – but – breaking changes are still breaking.

    Reply

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